Trigonal warping and anisotropic band splitting in monolayer graphene due to Rashba spin-orbit coupling
نویسندگان
چکیده
We study the electronic band structure of monolayer graphene when Rashba spin-orbit coupling is present. We show that if the Rashba spin-orbit coupling is stronger than the intrinsic spin-orbit coupling, the low-energy bands undergo trigonal-warping deformation and that for energies smaller than the Lifshitz energy, the Fermi circle breaks up into separate parts. The effect is very similar to what happens in bilayer graphene at low energies. We discuss the possible experimental implications, such as threefold increase in the minimal conductivity for low electron densities, anisotropic, wave-number-dependent spin splitting of the bands, and the spin-polarization structure.
منابع مشابه
Unravelling the mechanisms of giant spin-orbit splitting in graphene on metals
Weak interaction between graphene and metals tends to preserve the graphene’s characteristic Dirac cones almost intact in the band structure. However, recently it has been shown in experiments that even in case of very weak graphene/substrate coupling the presence of a heavy 5d metal can induce giant spin-orbit splitting (SO) of Rashba type in the graphene’s π bands, although the intrinsic SO c...
متن کاملDouble trigonal warping and the anomalous quantum Hall step in bilayer graphene with Rashba spin-orbit coupling.
We demonstrate that the trigonal warping observed in bilayer graphene is doubled in the presence of Rashba spin-orbit (RSO) coupling, i.e. the Dirac points along the three-fold symmetry axis are doubled. There are now seven Dirac points. Furthermore, the RSO interaction breaks the electron-hole symmetry of the magnetic band structure. The most intriguing feature is that the step of the quantum ...
متن کاملSpin-Orbit Coupling in Polariton Graphene: Optical Spin Hall Effect and Z Topological Insulator
We show that the TE-TM splitting of planar cavities leads to a special type of spin-orbit coupling for polariton graphene, a honeycomb superstructure formed by pillar microcavities, transforming into an emergent field with Dresselhaus symmetry at the Dirac points of the Brillouin zone. This transformation can be evidenced by the Optical Spin Hall effect. Under an applied magnetic field, polarit...
متن کاملSpin-dependent Klein tunneling in graphene: Role of Rashba spin-orbit coupling
Within an effective Dirac theory the low-energy dispersions of monolayer graphene in the presence of Rashba spin-orbit coupling and spin-degenerate bilayer graphene are described by formally identical expressions. We explore implications of this correspondence for transport by choosing chiral tunneling through pn and pnp junctions as a concrete example. A real-space Green’s function formalism b...
متن کاملSpin-orbit-mediated spin relaxation in monolayer MoS2
We study the intravalley spin-orbit-mediated spin relaxation in monolayers of MoS2 within a two bands effective Hamiltonian. The intrinsic spin splitting of the valence band as well as a Rashba-like coupling due to the breaking of the out-of-plane inversion symmetry are considered. We show that, in the hole doped regime, the out-of-plane spin relaxation is not very efficient since the spin spli...
متن کامل